The ability to prepare block, multiblock and segmented polymers is an essential and established tool in polymer chemistry to tailor the properties of materials and steer the formation of complex...

Synthetic polymers are indispensable in biomedical applications because they can be fabricated with consistent and reproducible properties, facile scalability, and customizable functionality to perform diverse tasks. However, currently available synthetic polymers have limitations, most notably when timely biodegradation is required. Despite there being, in principle, an entire periodic table to choose from, with the obvious exception of silicones, nearly all known synthetic polymers are combinations of carbon, nitrogen, and oxygen in the main chain. Expanding this to main‐group heteroatoms can open the way to novel material properties. Herein the authors report on research to incorporate the chemically versatile and abundant silicon and phosphorus into polymers to induce cleavability into the polymer main chain. Less stable polymers, which degrade in a timely manner in mild biological environments, have considerable potential in biomedical applications. Herein the basic chemistry behind these materials is described and some recent studies into their medical applications are highlighted.

We report a facile post‐polymerization modification route to functionalized aromatic polyimides via Diels‐Alder cycloaddition. Aromatic polyimides are important, versatile high‐performance polymers; however, their structural diversity is restricted by the requirements of the step‐growth polymerization. We prepared polyimides with alkynes in their main‐chain as macromolecular dienophiles and quantitatively grafted tetraphenylcyclopentadienone based dienes. The resulting solution‐processable, wholly aromatic polyimides show a considerable increase in surface area due to the induced conformational changes and bulky, rigid, and contorted molecular structures. The orthogonality of the reaction is exploited to insert functional groups, namely bromine and sulfonates, along the polymer backbone. In a further extension, the phenylene segments undergo cyclodehydrogenation to form nanographene segments within the polymer chains. The Diels‐Alder cycloaddition onto polyimides is therefore demonstrated to be an effective, widely applicable route to tunable high‐performance polymers with value‐added functionality and thus considerable potential in a wide range of advanced materials.

Photochemical additive manufacturing technologies can produce complex geometries in short production times and thus have considerable potential as a tool to fabricate medical devices such as individualized patient-specific implants, prosthetics and tissue engineering scaffolds. However, most photopolymer resins degrade only slowly under the mild conditions required for many biomedical applications. Herein we report a novel platform consisting of amino acid-based polyphosphorodiamidate (APdA) monomers with hydrolytically cleavable bonds. The substituent on the α-amino acid can be used as a handle for facile control of hydrolysis rates of the monomers into their endogenous components, namely phosphate and the corresponding amino acid. Furthermore, monomer hydrolysis is considerably accelerated at lower pH values. The monomers underwent thiol-yne photopolymerization and could be 3D structured via multiphoton lithography. Copolymerization with commonly used hydrophobic thiols demonstrates not only their ability to regulate the ambient degradation rate of thiol-yne polyester photopolymer resins, but also desirable surface erosion behavior. Such degradation profiles, in the appropriate time frames, in suitably mild conditions, combined with their low cytotoxicity and 3D printability, render these novel photomonomers of significant interest for a wide range of biomaterial applications.

Photochemical additive manufacturing technologies can produce complex geometries in short production times and thus have considerable potential as a tool to fabricate medical devices such as individualised patient-specific implants, prosthetics and tissue engineering scaffolds. However, most photopolymer resins degrade only slowly under the mild conditions required for many biomedical applications. Herein we report novel amino acid-based polyphosphorodiamidate (APdA) monomers with hydrolytically cleavable bonds. The substituent on the α-amino acid can be used as a handle for facile control of hydrolysis rates of the monomers into their endogenous components, namely phosphate and the corresponding amino acid. Furthermore, monomer hydrolysis is considerably accelerated at lower pH values. The monomers underwent thiol-yne photopolymerization and could be 3D structured via multi-photon lithography. Copolymerization with commonly used hydrophobic thiols demonstrates not only their ability to regulate the ambient degradation rate of thiol-yne polyester photopolymer resins but also rare but highly desirable surface erosion behaviour. Such degradation profiles, in the appropriate timeframes in suitably mild conditions, combined with their good cytocompatibility and 3D printability, render these novel photomonomers of significant interest for a wide range of biomaterial applications.